DRESS syndrome in a patient undergoing stem cell transplantation: Can sirolimus be involved?

We present a case of sirolimus-induced drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome in a stem cell transplant patient. Sirolimus is an immunosuppressive drug that inhibits the mammalian target of rapamycin (mTOR) pathway. A 24-year-old male with a history of acute lymphoblastic leukemia (ALL) underwent testicular extraction followed by hematopoietic stem cell transplantation (HSCT). He presented with pruritic eczematous lesions, which were initially treated with topical steroids. However, he later developed diffuse xerosis, fever, chills, generalized edema, weight gain, eosinophilia, and leukopenia. Skin biopsy showed spongiotic dermatitis with eosinophils, suggesting a drug or atopic reaction. Investigations ruled out infections, and the RegiSCAR score indicated drug reaction syndrome with eosinophilia and systemic symptoms (DRESS). Sirolimus, an immunosuppressive drug, was suspected as the cause. Sirolimus was discontinued, and oral steroids were initiated. After 3 weeks of therapy, the patient showed improvement with resolution of symptoms. Although no cases of sirolimus-induced DRESS syndrome have been reported, allergic reactions with eosinophilia induced by everolimus have been documented. In our case, the patient's history characterized by stem cell transplantation and multiple immunosuppressive therapies may have contributed to the development of DRESS syndrome after beginning sirolimus therapy. This case may be the first evidence of sirolimus-induced DRESS syndrome in a stem cell transplant patient.

Paraviral bullous eruption in a 7-year-old child during acute Epstein-Barr virus infection: A case report

We present the case of a child developing widespread vesicle-bullous lesions during an acute and symptomatic Epstein-Barr Virus infection. Antibody serology, biopsy, and direct immunofluorescence allowed the diagnosis of a paraviral bullous eruption. To our knowledge, this is the first report of bullous eruption following Epstein-Barr virus infection in childhood.

A Case of Lip Psoriasis in a 14-Year-Old Boy Successfully Treated with Adalimumab

Psoriasis is a common chronic skin disease mainly located in areas of friction. Psoriasis of the lips as an exclusive presentation is rare and often misdiagnosed. Different anti-psoriatic therapies have been proposed, but the literature is limited to case studies with partial results. Biologic therapies have revolutionized the management of many dermatologic conditions, including psoriasis, and they are approved for pediatric use. We report the case of a 14-year-old boy with a 2-year history of white-yellowish scaling lesions on his lips, without intraoral involvement. Lip biopsy showed a psoriasiform pattern. Treatment with adalimumab 40 mg every other week was started, and after 6 months of therapy, we obtained a complete remission of the patient's lip psoriasis.

Can erythema multiforme be an immune sequela of IgM nephropathy? A case report

A 13-year-old Chinese girl attended to our Pediatric Dermatology Unit for the appearance of itchy targetoid lesions on the trunk, face and upper limbs. A skin biopsy showed histological findings typical of erythema multiforme minor. A month earlier she was admitted for the onset of a nephrotic syndrome and the renal biopsy showed an IgM nephropathy with a diffuse mesangial cell proliferation. There was no medical history of recent infections, fever, muscle or joint pain, drugs intake related to erythema multiforme and viral serology were negative.

The role of antibodies in erythema multiforme could be more relevant than suspected and the severity of erythema multiforme was reported to be proportional to the antibody-mediated complement-dependent cytotoxicity, supporting the potential pathogenetic role for humoral immunity in this subtype of erythema multiforme.

We reported the first association of erythema multiforme and IgM nephropathy in a pediatric patient providing an additional hint that an antibody-mediated process, rather than T-cell cytotoxicity, might represent the main pathogenetic mechanism in certain subtypes of erythema multiforme.

A Misdiagnosed Desmoplastic Neurotropic Melanoma of the Scalp: A Challenging Case for the Pathologist and Surgeon

Desmoplastic neurotropic melanoma (DNM) is a rare melanoma subtype that shows tropism for the nerves, perineural invasion correlates to higher rate of local recurrence, poorer prognosis and worse morbidity. Given the paucity of typical melanoma features, both clinical and pathological, this confusing skin cancer may act as a pretender, thus leading clinician to misdiagnosis and subsequent inappropriate conservative treatment. Sarcomatoid-like cells rearrangement and absence of pigmentation can lead towards sarcoma diagnosis, so specific skills are required to pathologist to properly recognize this melanoma subtype. In this case report, we present an example of how challenging can be the diagnosis, and how it can affect clinical outcome.

Intratumor morphologic and transcriptomic heterogeneity in V600EBRAF-mutated metastatic colorectal adenocarcinomas

BACKGROUND

Intratumor heterogeneity (ITH) is described as the presence of various clones within one tumor, each with their own unique features in terms of morphology, inflammation, genetics or transcriptomics. Heterogeneity provides the fuel for drug resistance; therefore, an accurate assessment of tumor heterogeneity is essential for the development of effective therapies. The purpose of this study was to dissect morphologic and molecular ITH in colorectal adenocarcinoma.

MATERIALS AND METHODS

A series of 120 V600EBRAF-mutated (V600EBRAFmt) consecutive metastatic colorectal adenocarcinomas was assessed for morphologic heterogeneity. The two heterogeneous components of each specimen underwent a histopathological, immunohistochemical and molecular characterization to evaluate: histologic variant, grading, tumor-infiltrating lymphocytes (TILs), mismatch repair proteins' expression, KRAS/BRAF/NRAS mutations, microsatellite instability (MSI) status and consensus molecular subtype (CMS).

RESULTS

Thirty-one out of 120 (25.8%) V600EBRAFmt primary colorectal adenocarcinomas presented a heterogeneous morphology. Among these, eight cases had adequate material for molecular profiling. Five out of the eight (62.5%) cases resulted instable at MSI testing. The majority (62.5%) of the samples showed a CMS4 phenotype based on gene expression profiling. Heterogeneity in CMS classification was observed in four out of eight cases. One out of eight cases presented significant heterogeneity in the number of TILs between the two components of the tumor.

CONCLUSIONS

Although the distribution of the immune infiltrate appears relatively conserved among heterogeneous areas of the same tumor, changes in gene expression profile and CMS occur in 50% of V600EBRAFmt adenocarcinoma cases in our small series and might contribute to variability in response to anticancer therapy and clinical outcomes. Assessment of morphological and molecular ITH is needed to improve colorectal cancer classification and to tailor anticancer treatments and should be included in the pathology report.

The Molecular Landscape of Primary Acral Melanoma: A Multicenter Study of the Italian Melanoma Intergroup (IMI)

Acral melanoma (AM) is a rare and aggressive subtype of melanoma affecting the palms, soles, and nail apparatus with similar incidence among different ethnicities. AM is unrelated to ultraviolet radiation and has a low mutation burden but frequent chromosomal rearrangements and gene amplifications. Next generation sequencing of 33 genes and somatic copy number variation (CNV) analysis with genome-wide single nucleotide polymorphism arrays were performed in order to molecularly characterize 48 primary AMs of Italian patients in association with clinicopathological and prognostic features. BRAF was the most commonly mutated gene, followed by NRAS and TP53, whereas TERT promoter, KIT, and ARID1A were less frequently mutated. Gains and losses were recurrently found in the 1q, 6p, 7, 8q, 20 and 22 chromosomes involving PREX2, RAC1, KMT2C, BRAF, CCND1, TERT, and AKT3 genes, and in the 6q, 9, 10, 11q and 16q chromosomes including CDKN2A, PTEN, and ADAMTS18 genes, respectively. This study confirmed the variety of gene mutations and the high load of CNV in primary AM. Some genomic alterations were associated with histologic prognostic features. BRAF mutations, found with a higher rate than previously reported, correlated with a low Breslow thickness, low mitotic count, low CNV of the AMs, and with early-stage of disease.

Cutaneous manifestations in a series of 417 patients with SARS-CoV-2 infection: epidemiological and clinical correlates of chilblain like lesions

A variety of dermatological lesions have been described in COVID-19, although the prevalence and pathogenic relationship remain unclear particularly for chilblain-like lesions. Dermatological examination was performed in a prospective cohort of consecutive patients seen at the service for SARS-CoV-2 infection. Out of 417 patients with confirmed SARS-CoV-2 infection [median age 29.5 years (range 15-65); 62.5% males], dermatological lesions were detected in 7 (1.7%). Three patients had acral lesions; their age (range) was 15-29 years; all had a negative nasopharyngeal swab and developed IgG and/or IgM-specific antibodies; all presented none or mild symptoms. A fourth patient remained negative at repeated testing; mother, father and sister had a documented mild COVID-19. Non-acral lesions were observed in four older patients, with severe COVID-19. Chilblain-like lesions may be the sole manifestation of SARS-CoV-2 infection; their presence in asymptomatic school children and adolescents should be considered a potential signal of familial or community spread of the virus.

A novel KRT1 c.1433A>G p.(Glu478Gly) mutation in a newborn with epidermolytic ichthyosis

Epidermolytic Ichthyosis is a rare genodermatosis related to point mutations affecting the genes encoding for keratin 1 or keratin 10. We report a case of Epidermolytic Ichthyosis in a newborn with a novel mutation (c.1433A>G) of KRT1 gene.

Huriez syndrome associated with basal cell carcinoma. A case report

Huriez syndrome is a rare cancer-prone genodermatosis confined to the hands and feet connects with an increase in squamous cell carcinoma on affected skin. Its diagnosis is complex due to not well defined symptoms and since only few cases are described in literature. The differential diagnoses are many and the treatment is focused only on symptoms control and tumours eradication. Our case report is highly interesting because add new knowledge about this disease describing a new important feature of the syndrome. For the first time in literature we describe the arising of basal cell carcinoma from affected skin. KEY WORDS: H, Basal cell carcinoma, Huriez syndrome, Palmoplantar keratoderma.

Primary Central Nervous System Lymphomas: Clinicopathologic and Immunohistochemical Analysis of 30 Cases

Aims and background

Primary Central Nervous System lymphomas are attracting mounting interest because of their increasing incidence in an immunocompetent population and as sporadic tumors. A new lymphoma classification has been proposed, based on new morphologic entities and on advanced immunonologic and molecular techniques.

Methods and Results

The study concerns the clinical and pathologic characterization of 30 cases of primary central nervous system non-Hodgkin's lymphomas in non-HIV patients using a wide monoclonal antibodies panel. Comparative evaluation of effectiveness and reliability between surgery and stereotactic biopsies was made according to Kiel and Real lymphoma classifications. There were 24 high-grade and only 3 low-grade lymphomas. Three stereotactic biopsies were not diagnostic.

Conclusions

Stereotactic procedures were confirmed as the most immediate and least aggressive approach to CNS tumors, but inadequate sampling caused a deadlock to a full lymphoma diagnosis, which requires immunohistochemical and sometimes also molecular studies. However, it should be stressed that morphologic criteria (tumor cell cytology and neoplastic cuffing of the vascular walls) maintain their diagnostic effectiveness.

Inframammary Dermatitis: A Case of Localized Late-Onset Darier's Disease

Darier's disease (DD) is an autosomal dominant inherited genodermatosis which is often under- or misdiagnosed. In the majority of cases, the disease manifests in adolescents or young adults with small brownish-yellow, warty, hyperkeratotic papules in multiple seborrheic areas of the body. Localized DD (LDD) is a clinical variant, first described by Kreibich in 1906; only a few cases are reported in the literature. We described the case of an aged woman presenting with LDD, and we review the literature on this subject.

Plexiform fibromyxoma of the gallbladder

We report the unusual case of a plexiform fibromyxoma, occasionally assessed in a lithiasic gallbladder. The full thickness assessment of the gallbladder wall revealed an intra-mural, well demarked multi-nodular tumor (1 cm), consisting of a plexiform growth of spindle cells, included within a fibromyxoid stroma with a rich micro-vascular network. The tumor cells featured no nuclear atypia, nor mitotic activity. At the immunohistochemical profiling, the spindle shaped cells unequivocally featured vimentin, SMA, HHF35, collagen IV, and CD34; no cells expressed CD117, PDGFRA, CD10, desmin, GFAP, EMA, and S-100. Faint STAT6 nuclear expression was observed in isolated tumor cells. The molecular profiling did not revealed any CKIT and PDGFRA genes mutations. The uncommon site of the tumor presentation and its aberrant CD34 expression both confer to the reported case a unique place among the myxoid tumors of the gastrointestinal tract.

YAP immunoreactivity is directly related to pilomatrixoma size and proliferation rate

Organ size regulation is a highly coordinated process involving complex mechanisms. Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif, also known as WWTR1 (TAZ) have recently been linked to organ size determination and cell proliferation. Pilomatrixoma (PM) is a benign tumor of the adnexal appendages with a certain degree of differentiation toward the matrix of the hair follicle. PM presents as a dermal nodule that usually ranges from 0.5 to 2 cm, rarely exceeding 3 cm. We recently observed a case of unusual "giant" (6.5 cm) PM. Our hypothesis was that YAP and TAZ could be related to PM growth. We analyzed YAP and TAZ immunohistochemical expression in the giant and in ten usual size PMs in relation with tumor size and proliferation rate. YAP nuclear expression was remarkably higher in the giant PM in comparison with usual size PMs and statistically correlated, in a direct manner, with size and proliferation rate of PMs. Contrariwise, TAZ nuclear expression seemed stochastic. Our findings suggest that YAP could play a role in PM growth.

Human amniotic fluid stem cells protect rat lungs exposed to moderate hyperoxia

BACKGROUND

Treatment of bronchopulmonary dysplasia (BPD) remains as yet an unmet clinical need and recently stem cells have been proposed as a therapeutic tool in animal models. We investigated the role of amniotic fluid stem cells (AFS) in an adult rat model of hyperoxia lung injury.

METHODS

Fifty Sprague-Dawley rats were, at birth, randomly exposed to moderate hyperoxia or room air for 14 days and a single dose of human amniotic fluid stem (hAFS) or human Fibroblasts (hF), cells was delivered intratracheally (P21). At P42 animals were euthanized and lung tissue examined using histology, immunohistochemistry, PCR, and ELISA. hAFS cells characterization and homing were studied by immunofluorescence.

RESULTS

In rats treated with hAFS and hF cells 16S human rRNA fragment was detected. Despite a low level of pulmonary hAFS cell retention (1.43 ± 0.2% anti-human-mitochondria-positive cells), the lungs of the treated animals revealed higher secondary crest numbers and lower mean linear intercept and alveolar size, than those exposed to hyperoxia, those left untreated or treated with hF cells. Except for those treated with hAFS cells, moderate hyperoxia induced an increase in protein content of IL-6, IL-1β, as well as IF-γ and TGF-1β in lung tissues. High VEGF expression and arrangement of capillary architecture in hAFS cell group were also detected.

CONCLUSIONS

Treatment with hAFS cells has a reparative potential through active involvement of cells in alveolarization and angiogenesis. A downstream paracrine action was also taken into account, in order to understand the immunodulatory response.

Fluoxetine may worsen hyperoxia-induced lung damage in neonatal rats

Fluoxetine shows controversial lung effects as it prevents pulmonary hypertension in adult rats but exposure during gestation causes pulmonary hypertension in neonatal rats. In the present study, we tested the null hypothesis that the antidepressant drug fluoxetine does not modify the development of bronchopulmonary dysplasia (BPD) in neonatal rats. Experimental categories included I: room air (controls) with daily injection of saline; II: room air with daily injection of 10 mg/kg fluoxetine, i.p., during two weeks; III: 60% oxygen with daily injection of saline; and IV: 60% oxygen with daily injection of 10 mg/kg fluoxetine, i.p., during two weeks. Hyperoxia resulted in significant reduction in alveolar density and an increase in pulmonary endocrine cells, as well as increases in muscle layer areas of bronchi and arteries. Fluoxetine treatment generated a further increase in muscularisation and did not significantly modify the hyperoxia-induced reductions in alveolar density and increases in the endocrine cells. In hyperoxia, Real-Time PCR showed a lower pulmonary expression of vascular endothelial growth factor (VEGF) with no significant changes in the expression of matrix metalloproteinases (MMP) 2 and 12. Fluoxetine did not affect VEGF or MMP-2 expression but it significantly increased MMP-12 mRNA in both normoxic and hyperoxic groups. Zymographic analysis of MMP-2 activity in bronchoalveolar fluid showed a significantly reduced MMP-2 activity in hyperoxia, while fluoxetine treatment restored MMP-2 activity to levels comparable with the normoxic group. In conclusion, our data show that fluoxetine may worsen bronchial and arterial muscularisation during development of BPD and may up-regulate MMP expression or activity.

Verrucous sarcoidosis of the skin simulating squamous cell carcinoma

Here, we report a case of a 38-year-old woman with a history of systemic sarcoidosis who developed cutaneous verrucous sarcoidosis simulating a squamous cell carcinoma. This modality of presentation is unusual in both caucasic patients and in woman and may represent a diagnostic challenge for dermatologists.

"Double trouble" or an amplification of the triploidy phenotype?

Triploidy occurs in about 1 to 3% of clinically recognizable pregnancies and is typically associated with growth restriction, craniofacial dysmorphisms and congenital anomalies. We report the case of a female fetus with prenatal diagnosis of complete triploidy, polysplenia, bilateral cleft-palate, horseshoe-kidneys and bilateral club-feet. Whereas bilateral cleft-palate, horseshoe-kidneys and bilateral club feet are known to be part of the triploidy-associated malformation spectrum, polysplenia, which usually occurs as part of the heterotaxia spectrum, has never been associated with triploidy. An amplification of the triploidy phenotype or a "double trouble".

Occurrence of squamous cell carcinoma in an area of lichen simplex chronicus: case report and pathogenetic hypothesis

BACKGROUND

Lichen simplex chronicus is a common skin disorder characterized by circumscribed, lichenified, pruritic plaque secondary to local repetitive trauma, notably rubbing and scratching.

OBJECTIVE

We describe a case of a squamous cell carcinoma arising in a patient with a long-lasting history of lichen simplex chronicus and discuss the potential role of the microenvironment in predisposing the malignant transformation.

CONCLUSION

Here we propose a hypothesis in which rubbing and scratching contribute to an excess of inflammatory mediators, which in turn may lead to alterations in the processes of keratinocyte proliferation and differentiation.

Apert syndrome with fused thalami

Apert syndrome (Acrocephalosyndactyly type I; AS) is a rare but well-known autosomal dominant disorder characterized by craniosynostosis, midface hypoplasia, bony/cutaneous syndactyly of fingers and toes as well as a variety of associated congenital anomalies involving the brain, heart, limbs and other organ systems. We report the case of a fetus with molecularly confirmed Apert syndrome and additional fusion of the thalamic nuclei. Various central nervous system anomalies, have been reported in patients with AS. However, as far as we know cases of fused thalami in Apert syndrome have never been reported so far.

Pentalogy of cantrell with complete ectopia cordis in a fetus with asplenia

Cantrell's pentalogy (CP) is a rare, mainly sporadic spectrum of congenital midline thoracoabdominal defects that includes sternal anomalies, ventral diaphragmatic hernia, partial absence of the pericardium, supraumbilical abdominal wall defects, and congenital heart malformations. The approximate incidence is 1 in 100 000, with a 2∶1 male predominance. A 25-year-old pregnant woman was referred to the Prenatal Diagnosis Unit of the University Hospital of Padua for multiple congenital malformations at 21 weeks of gestation. A level 2 ultrasound scan was performed and confirmed the presence of multiple anomalies compatible with the diagnosis of CP associated with complete ectopia cordis. Fetal autopsy furthermore revealed asplenia, which usually presents as part of the heterotaxia spectrum. To our knowledge, an association of CP and complete ectopia cordis with asplenia has never been reported so far.

Congenital pulmonary airway malformation (CPAM) [congenital cystic adenomatoid malformation] associated with tracheoesophageal fistula and agensesis of the corpus callosum

Congenital pulmonary airway malformations (CPAM) are a family of hamartomatous disorders due to the uncontrolled overgrowth of the terminal bronchioles. Congenital pulmonary airway malformations can co-exist with cardiovascular and/or urogenital malformations, but their association with thoracopulmonary malformations is extremely rare. We report the first case of CPAM type I, co-existing with tracheo-esophageal fistula and corpus callosum agenesis.

Malignant Glomus Tumor of the Leg Developed in the Context of a Superficial Typical Glomus Tumor

A 41-year-old man presented with a 2-cm painful subcutaneous nodule in his right leg, which had been present for more than 10 years and was recently enlarging. Histologically, the tumor was composed of sheets and nests of cells with variable cytomorphology, including typical round/ovoid glomus cells with clear cytoplasm and well-defined borders, small cells, and spindle cells. Numerous medium to large vessels were present. Nodules with moderate to high cellularity, nuclear atypia, and frequent mitotic figures (42 per 50 high-power fields) were noted. Immunohistochemistry showed cytoplasmic and membranous expression of smooth-muscle actin, vimentin, and membranous expression of type IV collagen. Whereas superficiality, dimensions, and long-term follow-up may suggest classification as a symplastic or uncertain potential glomus tumor (GT), histological features and immunoprofile are indicative of malignant nodules developed in a typical GT. The follow-up has been negative for recurrence/metastases. A search of the literature revealed 17 cases of malignant GTs between 1995 and 2010, all fatal, of which 10 had skin as the primary site.

Masson's disease in hand surgery: a clinicopathologic study of four cases

Intravascular papillary endothelial hyperplasia (IPEH), also known as Masson's tumour, is an uncommon benign vascular lesion characterized by small multiple, endothelial-lined, papillary structures with hyaline stalks. It appears to be a reactive condition involving excessive proliferation of endothelial cells in normal blood vessels or in vascular malformations, perhaps in response to blood vessel injury or thrombosis. The lesions are small, superficial, reddish-blue nodules, usually in the head, neck or hand. Distinction from pyogenic granuloma and angiosarcoma usually requires pathological examination. Complete surgical excision is the treatment of choice. Four cases affecting the finger are presented together with histological features.

Histological evolution of chronic wounds under negative pressure therapy

BACKGROUND

Negative pressure wound therapy (NPT) has achieved widespread success in the treatment of difficult wounds. However, its effects are but partially explored, and investigations mostly concentrated at the wound-dressing interface; a detailed histological description of the evolution of wounds under NPT is still lacking.

MATERIALS AND METHODS

Subsequent punch biopsies of NPT-treated chronic wounds of human patients were analysed. Phenomena occurring in wounds were quantified by analysis of proliferating cells nuclear antigen (PCNA) (proliferating nuclei), CD31 (blood vessels), CD68p (macrophages) and CD45 (lymphocytes) stained slides.

RESULTS

Three layers were identified in day-0 wounds. Over time, under NPT, the layers behaved differently: the most superficial (1.5 mm) developed granulation tissue, constant in thickness, with high proliferation index, increased in blood vessels density and developed acute inflammation. Instead, the two deeper layers decreased in proliferation rate, maintained vessels density unchanged, were cleared of chronic inflammation and oedema and underwent progression towards stable tissue.

DISCUSSION

Indeed, while most research has focused on induction of superficial granulation tissue by NPT, deeper layers appear to be also affected, with relieving of chronic inflammation and tissue stabilisation. This may be an important and under-appreciated effect, playing a role in the known positive outcomes of NPT, such as better graft-taking rates.

Fetal aorta wall inflammation in ultrasound-detected aortic intima/media thickness and growth retardation

Several studies have reported that fetuses with intrauterine growth restriction (IUGR) and infants with low birth weight present increased intima/media thickness (aIMT) of the abdominal aorta wall compared with fetuses and infants appropriate for gestational age (AGA). Evidence suggested that aIMT might be related to inflammation, probably indicating a very early stage of future adulthood disease, such as atherosclerosis. We aimed to investigate histological findings in the abdominal aorta wall of one IUGR stillbirth in which ultrasound had detected aIMT. Microscopy observations of the abdominal aorta wall confirmed the intima thickening and detected condensation of the elastic fibers forming an evident internal elastic membrane and presence of inflammatory elements, such as macrophages, activated endothelial cells, and fibroblastoid cells. The present study highlights that IUGR associated with aIMT is related to inflammation, which might represent a very early sign of future adult lesions.

Bullous scabies simulating pemphigoid

BACKGROUND

Scabies is a contagious infestation affecting subjects of all ages, races, and social conditions.

OBJECTIVE

We report a case of a 79-year-old man who developed a bullous pemphigoid-like eruption. He presented to our unit 4 months after the onset of symptoms. An autoimmune bullous disease was suspected. Direct immunofluorescence on a skin specimen and anti-desmoglein 1, anti-desmoglein 3, and anti-bullous pemphigoid antigen 180 were negative. Surprisingly, the histology of a skin lesion demonstrated the presence of scabies, which was successfully treated with benzyl benzoate 20%.

CONCLUSION

The diagnosis of bullous scabies should be considered for any bullous eruptions accompanied by papules and itching resistant to steroid treatment and with negative immunopathologic findings.